Cetylpyridinium Chloride Mouthwash to Reduce Shedding of Infectious SARS-CoV-2: A Double-Blind Randomized Clinical Trial.

The airborne transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) via respiratory fluids and droplets suggests that mouthwashes containing substances with virucidal activity can help reduce viral spread. We conducted a multicenter, double-blind, placebo-controlled, randomized trial to assess the virucidal activity of cetylpyridinium chloride (CPC) mouthwashes. Outpatients who tested positive for SARS-CoV-2 infection with or without symptoms were randomized to perform washes and gargles for 1 min with 15 mL of either colored distilled water or 0.07% CPC (Vitis CPC Protect) mouthwash. The study outcomes were the SARS-CoV-2 log10 viral RNA load and the nucleocapsid protein levels, both in saliva at 1 and 3 h after the intervention. In total, 118 patients were enrolled and randomized (mean [SD], age 46 [14] y). Thirteen of 118 participants (11%) did not complete follow-up or had insufficient sample volume for testing and were excluded from the analysis. The assessment of the viral load showed no significant differences between groups at any of the investigated points. However, the levels of SARS-CoV-2 nucleocapsid protein of lysed viruses were significantly higher in the CPC group compared with the control group at 1 h (adjusted difference 269.3 pg/mL; 95% confidence interval [CI], 97.1-441.5) and at 3 h postintervention (561.1 pg/mL; 95% CI, 380.0-742.2). In nonhospitalized patients with asymptomatic or mild symptomatic SARS-CoV-2 infection, a 0.07% CPC mouthwash, compared to placebo, was associated with a significant increase of nucleocapsid protein levels in saliva, indicating enhanced disruption of viral particles.

Electrochemical genosensor for Klotho detection based on aliphatic and aromatic thiols self-assembled monolayers.

Changes in expression of Klotho gene are associated with chronic kidney disease and its potential as early biomarker is being studied. We report, for the first time, the detection of Klotho gene by a biosensor platform. Self-assembled mixed monolayers (SAMs) as DNA immobilization method in screen-printed gold electrodes and a sandwich format detection were used in the development of an electrochemical genosensor for the detection of a 100-mer DNA fragment, copy of the partial region of the mRNA Klotho gene. The use of different binary and ternary SAMs based on aliphatic (mercaptohexanol, MCH, and hexanedithiol, HDT) and aromatic (mercaptophenylacetic acid, MPAA) thiol diluents and capture probe (CP) as sensing phases was evaluated by cyclic voltammetry and electrochemical impedance spectroscopy. Multiple configurations were studied, changing the order of component addition and comparing co-immobilization and two-step immobilization processes. The procedure for binary SAM preparation consisting of sequential addition of a thiol diluent followed by CP was found to have the least detrimental impact on electrochemical performance. The signal-to-blank ratios increased considerably in the case of thioaromatic binary DNA monolayers, MPPA/CP, compared to the values obtained for aliphatic SAMs. Ternary monolayers formed by MCH and HDT rendered good fractional coverage levels and generated more reversible redox reactions at the surface, mostly when CP was firstly immobilized, CP/HDT/MCH. A significant reduction of the blank and non-specific (non-complementary sequence) signals was obtained with this ternary SAM, compared to binary SAMs and an increase of 2.42-fold of the S/B ratio (10 nM of target) compared with MPAA/CP SAMs. A linear response in the range of 5·10-10 to 5·10-8 M was obtained with CP/HDT/MCH monolayer, with a detection limit of 0.5 nM and RSD of 8.10%.